A semiconductor light emitting element, such as a laser diode (LD) or a light emitting diode (LED), is widely used in a display device, an illumination device, and a recording device. In recent years, solid-state illumination is developed as a new application. In particular, a backlight source of an illumination device or a liquid crystal display device is replaced by a white light emitting device obtained by combining the semiconductor light emitting element and a fluorescent substance.
For example, a liquid crystal display device is miniaturized for a portable apparatus. Also, miniaturization is needed in a light emitting device used in the backlight source.